1. Field of the Invention
This invention relates to oral hygiene implements.
Most people clean their teeth often, even if not as often or for as long as dentists recommend.
Although practised to some extent nowadays, but not widely, cleansing of the tongue has been practised for thousands of years, at least as far back as the Egyptians, who realised the importance of a clean tongue. The surface of the tongue has sensory taste receptor cells, or taste buds, which determine how bitter, salty, sweet or sour things that we consume taste. Undisturbed saliva, bacteria and food debris in the mouth eventually turn into plaque. Once plaque has formed, it causes tooth decay, gum disease and halitosis, or bad breath. A build-up of plaque on the tongue's taste buds can result in them not functioning fully and a loss of taste sensitivity. Smoking has a similar effect. No matter how often somebody cleans their teeth, a coating of plaque, food debris, etc. remains on their tongue unless it is also removed.
2. Description of the Prior Art
Strigils are known for scraping the tongue to remove the coating thereon. It is also known to provide a combined tongue strigil and toothbrush. In this connection, patent document DE 29819064U 1 shows a toothbrush having a scraping edge along a corner of the cross-section of its handle. A disadvantage of this is that the scraping edge will tend to cut into the user's fingers or thumb, or at least be uncomfortable, when the device is being used as a toothbrush. To deal with this problem, patent document U.S. Pat. No. 5,005,246 describes a toothbrush with a tongue scaler which can be extended, when required, from a channel within the toothbrush handle and which has an edge for scraping the tongue. Disadvantages of this are that the device is complicated and the channel inside the toothbrush handle provides a hiding place for bacteria and other matter removed from the tongue. Furthermore, patent document U.S. Pat. No. 4,356,585 describes a toothbrush with a spoon-like formation part-way along its handle. Part of the rim of this formation is intended to be used for scraping the tongue. A disadvantage of all three of these known devices is that they either cannot be used, or can only be used with great difficulty, to scrape the rear of the tongue. Also, patent document U.S. Pat. No. 5,709,004 describes a combined toothbrush and tongue scraper which is formed generally like a pair of tongs. The end of each tong is provided with half of the toothbrush head and the tongs can be clipped together for use as a toothbrush. When the tongs are unclipped, each tong is used as a handle, and the part of the device joining the tongs forms the tongue scraper. Disadvantages of this device are that it is of complicated construction, and bacteria and other matter removed from the tongue can collect between the tongs and in the elements used for clipping the tongs together.